A group of five suspected militants were stopped at the Sydney airport on August 12, with two of the five attempting to leave again the next day, as media reported.

"We are concerned about the number of people presenting at airports, particularly younger people, who might be seeking to travel overseas for reasons that would horrify Australians and their parents and family and community no doubt as well," Dutton said.

Prime Minister Tony Abbott said the 'important and significant' operation demonstrated the 'vigorous' action being taken by Australian authorities domestically and overseas to disrupt the movement of foreign fighters.

"We have stopped at the airport, seven young Australians who were planning to travel to the Middle East, it seems to join terrorist groups over there," the Prime Minister said.

"This indicates the continuing allure of this death cult. It shows the importance of the most vigorous action at home and abroad to disrupt, to degrade, to destroy this menace to the freedom and the security of the world," Abbot added.

Australian government estimates there are more than 120 Australians fighting with terror groups in Syria and Iraq.